Warpage compensating rf shield frame

ABSTRACT

An integrated circuit package shield comprising a frame comprising two or more segments, the segments to interlock with one another along a substrate and the segments comprising electrically conductive material to electrically couple to the substrate; and a lid to cover the frame, the lid comprising a conductive material to electrically couple to the substrate.

CLAIM FOR PRIORITY

This application is a continuation of, and claims the benefit ofpriority to U.S. patent application Ser. No. 15/937,246, filed on Mar.27, 2018, titled “WARPAGE COMPENSATING RF SHIELD FRAME”, which isincorporated by reference in its entirety for all purposes.

BACKGROUND

During manufacturing of integrated circuit (IC) packaging warpage of thepackage substrate can break solder joints causing open connectionsbetween components such as IC dies to the metallization on the packagesubstrate. For radio frequency integrate circuits (RFIC), a groundedshield may be integrated into the package to mitigate electromagneticinterference due to RF generation by the RFIC components on board thepackage. Suppliers of RF shields specify coplanarities of 100 microns orless. The large non-planarity of the shield combined with substratewarpage, as well as possible warpage of the shield itself, can result inbreakage of solder joints connecting the RF shield to the groundmetallization of the package. Failure of the shield ground connectionsreduces the efficacity of the shield to contain RF energy within thepackage, resulting in significantly lower yields of RFIC packages.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments of the disclosure will be understood more fully from thedetailed description given below and from the accompanying drawings ofvarious embodiments of the disclosure, which, however, should not betaken to limit the disclosure to the specific embodiments, but are forexplanation and understanding only.

FIG. 1A illustrates a plan view in the x-y plane of an embodiment of awarpage compensating RF shield frame over a package substrate, accordingto some embodiments of the disclosure.

FIG. 1B illustrates a profile view in the x-z plane of the embodiment ofa warpage compensating RF shield frame over a package substrate shown inFIG. 1A, according to some embodiments of the disclosure.

FIG. 2A illustrates a plan view in the x-y plane of an embodiment of awarpage compensating RF shield frame over a package substrate, accordingto some embodiments of the disclosure.

FIG. 2B illustrates a profile view in the x-z plane of the embodiment ofa warpage compensating RF shield frame over a package substrate shown inFIG. 2A, according to some embodiments of the disclosure.

FIG. 3A illustrates a plan view in the x-y plane of an embodiment of awarpage compensating RF shield frame over a package substrate, accordingto some embodiments of the disclosure.

FIG. 3B illustrates a profile view in the x-z plane of the embodiment ofa warpage compensating RF shield frame over a package substrate shown inFIG. 3A, according to some embodiments of the disclosure.

FIG. 4A illustrates a plan view in the x-y plane of an embodiment of awarpage compensating RF shield frame over a package substrate, accordingto embodiments of the disclosure.

FIG. 4B illustrates a profile view in the x-z plane of the embodiment ofa warpage compensating RF shield frame over a package substrate shown inFIG. 4A, according to some embodiments of the disclosure.

FIG. 5A illustrates a plan view in the x-y plane of a warpagecompensating RF shield assembly comprising an RF shield lid and an RFshield frame, according to some embodiments of the disclosure.

FIG. 5B illustrates a profile view in the x-z plane of separatedcomponents of a warpage compensating RF shield assembly 500 comprisingRF shield lid and RF shield frame, according to some embodiments of thedisclosure.

FIG. 5C illustrates a profile view in the x-z plane of a warpagecompensating RF shield assembly in the assembled state, according tosome embodiments of the disclosure.

FIG. 6 illustrates a flow chart summarizing an exemplary method forforming a warpage compensating RF shield frame, according to embodimentsof the disclosure.

FIGS. 7A-7G illustrate a progression of operations comprised byexemplary method for making a warpage compensating RF shield frame,according to some embodiments of the disclosure.

FIG. 8 illustrates an IC package having a warpage-compensating RF shieldframe, fabricated according to the disclosed method, as part of asystem-on-chip (SoC) package in an implementation of computing device,according to some embodiments of the disclosure.

DETAILED DESCRIPTION

In the following description, numerous details are discussed to providea more thorough explanation of embodiments of the present disclosure. Itwill be apparent, however, to one skilled in the art, that embodimentsof the present disclosure may be practiced without these specificdetails. In other instances, well-known structures and devices are shownin block diagram form, rather than in detail, in order to avoidobscuring embodiments of the present disclosure.

Radio frequency integrated circuits (RFICs) require careful shielding toprevent electromagnetic interference (EMI) with nearby integratedcircuits (ICs) or devices. Presently, packages conceived for RFICsinclude an RF shield which may be soldered to the ground plane or traceson the package board or substrate. The shield may comprise a frame andlid structure, where the frame is attached by solder to the packagesubstrate board. For the RF shield to be effective, it must remainelectrically coupled to the package ground circuit metallization duringthe life of the IC. However, warpage of the IC package substrate, whichgenerally occurs after solder reflow operations, may result in opensolder joints due to coefficient of thermal expansion (CTE) mismatchbetween the shield and substrate materials. In addition, coplanarity ofstandard mass-produced RF shields is generally not better than 100microns. This level of shield co-planarity may exacerbate the occurrenceof open solder joints due to substrate warpage.

Package architectures that include RF shields conventionally include ametal lid-like structure that attaches (i.e., by soldering to the groundmetallization) to the package substrate and covers all components bondedto the substrate, such as IC dies and discrete components. In someinstances, a shield frame is included with the lid forming a shieldassembly. The frame may be directly soldered to the substrate, while thelid is fitted over the frame.

As damage to the integrity of the shield/substrate bond, generally inthe form of open solder joints, can result from warpage that strains thesolder joints, attempts to mitigate such loss of shield integrity haveincluded the use of thicker substrate and/or thicker shield frame toreduce warpage. However, package height restrictions may preclude thisapproach, as it counters current trends to reduce package dimensions,particularly in the z-dimension. Other approaches, such as a more bruteforce example of adding more solder paste to strengthen the solderjoint, have not presented robust solutions as solder wicking between thelid and frame has been observed.

Large coplanarity, along with substrate warpage can result in opensolder joints or shield fall off during reflow. Use of more expensiveshield materials also have been considered, where the materials exhibitless warpage or better co-planarity. However, this approach runs counterto requirements to reduce cost of integrated circuits. Another approachhas been to divide the frame into two sections in order to compensatesubstrate warpage by independently attaching the two sections to eachhalf of the substrate, and allowing the separate sections toindependently follow the relative bending of each half of the substrate.However, it has been observed that the two frame sections spread duringreflow, exceeding frame dimension tolerances. In addition, warpagegenerally occurs at the corners of the substrate, and not at the edges.

A robust warpage-compensating RF shield frame is disclosed herein thatovercomes the afore-mentioned limitations. Embodiments of the disclosedRF shield frame comprises multiple interlocking frame sections. In someembodiments, the disclosed RF shield frame comprises four interlockingsections, attached to the four corners of the substrate. Theinterlocking frame sections comprise interdigitating interfaceextensions that restrict lateral motion of the sections during reflow.As substrate warpage generally occurs at the corners of the substrate,attachment of four shield frame sections over the corners allows theframe to follow the warpage at the substrate corners.

The disclosed warpage-compensating RF shield frame provides a mountingstructure for a lid to complete the shield. The lid may cover IC diesand discrete components attached to the package substrate. In someembodiments, the lid comprises slots that align with raised embossmentson the frame to lock the lid on the frame. The embossments projectthrough the slots, locking the lid to the frame. Movement of the lidrelative to the frame is restricted during subsequent package assemblyoperations, such as encapsulation. In some embodiments, the lid issoldered to the frame.

Assembly of the frame may be carried out by pick and place operations,according to some embodiments. The frame segments are placed eitherone-by-one, or simultaneously, over the substrate. In some embodiments,each of four frame segments have one or more interlocking sections toassemble into a frame along the edges of a rectangular substrate. Theinterlocking sections comprise finger-like extensions or protrusions. Insome embodiments, interlocking frame segments comprise two interlockingsections that have protrusions that interlock by interdigitation. Insome embodiments, each frame segment comprises two interlockingsections. The protrusions of each of the two interlocking sections of afirst frame segment interdigitate with those of a second and thirdmating frame segments. The second and third mating frame segmentsinterlock with fourth frame segment to complete the frame surroundingthe rectangular substrate. In some embodiments, the interlockingsections interdigitate along each of the four edges between corners. Inthis way, the four frame segments may articulate independently about thejoints formed by the interlocking sections following the warpage of thesubstrate, which tends to bend at the corners.

In addition to providing a point of articulation for the independentmovement of the individual frame segments, the joints formed by theinterlocking sections restrict lateral motion of the frame segments.Without the safeguard of the interlocking sections, lateral motion ofthe frame segments may occur during solder reflow by surface tension,for example, causing an offset of the frame segments relative to thesubstrate edges. The dimensional tolerances may be exceeded byunrestricted movement of the frame segments, thereby preventing the lidto be fitted over the substrate. In some embodiments, the seam thatseparates the interdigitated protrusions has a maximum separationtolerance of 50 microns. In some embodiments, the separation toleranceis 20-30 microns.

In some embodiments, a single protrusion follows a complementaryindentation (to allow a mating protrusion to interdigitate). In someembodiments, the protrusions and complementary indentations are rounded.A meandering or S-shaped curve may define the protrusion and indentationpair on an interlocking section of a frame segment. In some embodiments,the protrusions and indentations are pointed. A single protrusionfollows a complementary indentation, forming a N-shaped or zig-zagshaped protrusion and indentation pair.

In some embodiments, the protrusion shape is rectilinear. A rectilinearmeander may define the protrusion and indentation pair. In someembodiments, the protrusion is an oval or circular tab on one framesegment that fits into a complementary indentation on a mating framesegment.

In some embodiments, frame segments comprise one or more elongatestructural members that extend from edge members. When placed on asubstrate, the one or more elongate structural members extend over thesurface of the substrate. In some embodiments, the one or more elongatestructural members extend diagonally from the edge members. In someembodiments, a first diagonal elongate structural member extends fromthe distal end of a first edge member and terminate at the distal end ofthe second edge member, forming a triangle in the x-y plane. In someembodiments, a second diagonal elongate structural member extends fromthe corner to terminate at a point along the first diagonal structuralelongate member. In some embodiments, a touch-down pad is affixed to oneor more of the elongate structural members. The touch-down pad providesa surface for a pick and place nozzle suction cup to touch down and lifta frame segment.

In some embodiments, the one or more elongate structural members extendorthogonally from the edge members. In some embodiments, two elongatestructural members intersect at their distal ends, forming a rectanglewith the orthogonal edge members in the x-y plane.

A method of forming a RF shield is also disclosed. The method comprisesplacing pre-reflow solder over ground circuitry metallization on apackage substrate. In some embodiments, solder balls are attached to theground circuitry metallization. In some embodiments, solder paste isapplied over the ground circuitry metallization. The method furthercomprises the placement of one or more shield frame segments over thepackage substrate. In some embodiments the one or more shield framesegments are placed over the package substrate by pick and placetechniques. The method further comprises placing the frame segments overthe substrate in such a way that the that the segments interlock byinterdigitation as described above. The method further comprisesreflowing the solder to permanently bond the shield frame to thesubstrate. The bonding is both mechanical and electrical, as the shieldframe is coupled to the ground circuitry of the substrate.

Throughout the specification, and in the claims, the term “connected”means a direct connection, such as electrical, mechanical, or magneticconnection between the things that are connected, without anyintermediary devices.

The term “coupled” means a direct or indirect connection, such as adirect electrical, mechanical, or magnetic connection between the thingsthat are connected or an indirect connection, through one or morepassive or active intermediary devices.

Here, the term “package” generally refers to a self-contained carrier ofone or more dies, where the dies are attached to the package substrate,and encapsulated for protection, with integrated or wire-bonedinterconnects between the die(s) and leads, pins or bumps located on theexternal portions of the package substrate. The package may contain asingle die, or multiple dies, providing a specific function. The packageis usually mounted on a printed circuit board for interconnection withother packaged ICs and discrete components, forming a larger circuit.

Here, the term “dielectric” generally refers to any number ofnon-conductive materials that make up the structure of a packagesubstrate. For purposes of this disclosure, dielectric material may beincorporated into an IC package as layers of laminate film or as a resinmolded over IC dies mounted on the substrate.

Here, the term “metallization” generally refers to metal layers formedover the dielectric material of the package substrate. The metal layersare generally patterned to form metal structures such as traces and bondpads. The metallization of a package substrate may be confined to asingle layer or in multiple layers separated by layers of dielectric.

The term “circuit” or “module” may refer to one or more passive and/oractive components that are arranged to cooperate with one another toprovide a desired function. The term “signal” may refer to at least onecurrent signal, voltage signal, magnetic signal, or data/clock signal.The meaning of “a,” “an,” and “the” include plural references. Themeaning of “in” includes “in” and “on.”

The vertical orientation is in the z-direction and it is understood thatrecitations of “top”, “bottom”, “above” and “below” refer to relativepositions in the z-dimension with the usual meaning. However, it isunderstood that embodiments are not necessarily limited to theorientations or configurations illustrated in the figure.

Relative distances at times may be indicated by the terms “proximal” and“distal” when referring to elongate structures in particular. “Distal”may refer to a point at or near the end of an elongated structure thatis extended furthest from other structures near the “proximal” end ofthe elongate structure. “Proximal” may refer to the origin of thestructure, for example, wherefrom the elongate structure extends (e.g.,“edge members extending from a corner”, where the corner is the origin).

The terms “substantially,” “close,” “approximately,” “near,” and“about,” generally refer to being within +/−10% of a target value(unless specifically specified). Unless otherwise specified the use ofthe ordinal adjectives “first,” “second,” and “third,” etc., to describea common object, merely indicate that different instances of likeobjects are being referred to, and are not intended to imply that theobjects so described must be in a given sequence, either temporally,spatially, in ranking or in any other manner.

For the purposes of the present disclosure, phrases “A and/or B” and “Aor B” mean (A), (B), or (A and B). For the purposes of the presentdisclosure, the phrase “A, B, and/or C” means (A), (B), (C), (A and B),(A and C), (B and C), or (A, B and C).

Views labeled “cross-sectional”, “profile” and “plan” correspond toorthogonal planes within a cartesian coordinate system. Thus,cross-sectional and profile views are taken in the x-z plane, and planviews are taken in the x-y plane. Typically, profile views in the x-zplane are cross-sectional views. Where appropriate, drawings are labeledwith axes to indicate the orientation of the figure.

FIG. 1A illustrates a plan view in the x-y plane of RF shield frame 100over a package substrate, according to some embodiments of thedisclosure.

In FIG. 1A, RF shield frame 100 comprises frame segments 101 thatinterlock together. FIG. 1A depicts four interlocking frame segments 101a, 101 b, 101 c and 101 d, distributed about the four edges of packagesubstrate 102. In some embodiments, interlocking frame segments 101 a-dare mechanically and electrically coupled to substrate 102. In someembodiments, interlocking frame segments 101 a-d are solder-bonded tothe ground metallization of substrate 102 (including a ground plane, notshown). In the illustrated embodiment, each of the frame segments 101a-d comprise orthogonal edge members 103 and elongate structural members104, extending diagonally over portions of substrate 102. In theillustrated embodiment, frame segments 101 a-d comprise three diagonalelongate structural members 104 that extend from edge members 103. Thethree elongate members 104 terminate at a common point. In someembodiments, pads 105 are disposed along elongate structural members104. Pads 105 may be employed to provide a surface for pick-and-placenozzle suction cup touch-down.

In some embodiments, frame segments 101 a-101 d comprise conductivematerials such as copper, nickel and beryllium. In some embodiments,frame segments comprise sheet metal comprising the copper, nickel andberyllium having thickness ranging from 100 to 500 microns.

Frame segments 101 a and 101 b comprise two interlocking sections 106 aand 106 b, respectively, disposed at the distal ends of edge members 103a and 103 b, respectively. For the embodiment depicted in FIG. 1A, amagnified view of adjacent interlocking sections 106 a and 106 b isshown within the zoom window (interlocking interface 107 encircledwithin dashed circle). The adjacent interlocking sections 106 a and 106b comprise interdigitating protrusions 108 a and 108 b, respectively. Insome embodiments, interlocking sections (e.g., 106 a and 106 b) comprisemultiple interdigitating protrusions (e.g., 108 a and 108 b). Theinterdigitating protrusions 108 a and 108 b restrict lateral movement inboth the x and y directions of frame segments 101 a and 101 b. Forexample, lateral motion of frame segments 101 a and 101 b may occurduring solder reflow, allowing the frame segments to move apart beyondthe lateral tolerance of the package.

In the illustrated embodiment, interdigitating protrusions 108 a and 108b are rounded, having an S-shaped boundary. A gap may exist within theboundary, where the gap separation is the distance d₁ denoted in FIG.1A. In some embodiments, the distance d₁ is 50 microns. In someembodiments, distance d₁ is less than 50 microns. While the interlockinginterfaces of frame segments 103 a and 103 b were described in detailabove, each frame segment comprises two interlocking sections at thedistal ends of the corresponding edge members, similar to 106 a and 106b.

The boundary between the interdigitated protrusions may provide anarticulating joint between adjacent frame segments (e.g., 101 a and 101b), allowing a degree of freedom of motion in the z-direction of framesegments 101 a-d to follow out-of-plane warpage of substrate 102. Thefour frame segments 101 a-d may articulate independently at the jointsformed within each of the four interlocking interfaces 107, 109, 110 and111, allowing flexible warpage adjustment of RF shield frame 100. Theneed to match CTE or utilize thick RF shield frames and/or packagesubstrates to mitigate damage to the bond integrity of the RF shield dueto substrate warpage may be obviated by the employment of a flexible RFframe comprising articulating joints.

The interdigitated portion (comprising protrusions 108 a and 108 b)shown in the magnified view of interlocking interface 107 may berepeated for each interlocking interface 109, 110 and 111. Framesegments 101 a interfaces with both frame segment 101 b and 101 c. Thecorresponding interlocking interfaces 107 and 111, respectively, aredenoted by dashed circles. Similarly, frame segment 101 b interfaceswith frame segment 101 d (interlocking interface 109), and frame segment101 d interfaces with frame segment 101 c (interlocking interface 110).The four interlocking interfaces 107, 109, 110 and 111 couple togetherthe four frame segments 101 a-d of RF shield frame 100 in a mannersubstantially the same as described in detail for interlocking interface107. In some embodiments, embossments 112 are provided to aid in shieldlid attachment (not shown) to RF shield frame 100, as described below.

FIG. 1B illustrates a profile view in the x-z plane of RF shield frame100 over a package substrate, according to some embodiments of thedisclosure.

FIG. 1B shows details in the x-z plane of frame members 103 a and 103 bof frame segments 101 a and 101 b, respectively. These details may berepeated for frame members 101 c and 101 d, not shown in FIG. 1B. Framemembers 103 a and 103 b extend a distance d₂ in the x-z plane,corresponding substantially to the thickness of frame members 103 a and103 b. Embossments 112 are shown in profile on the top portions of framemembers 103 a and 103 b, extending a distance d₃ above the edge members103 a and 103 b. In some embodiments, embossments 112 are provided toalign with slots on a mating lid (described below and shown in FIG. 5A).

A profile view of interlocking interface 107 is shown in the circledregion, encompassing interlocking sections 106 a and 106 b. The gapbetween interlocking sections 106 a and 106 b is shown and denoted bydistance d₁.

FIG. 2A illustrates a plan view in the x-y plane of RF shield frame 200over a package substrate, according to some embodiments of thedisclosure.

In FIG. 2A, RF shield frame 200 comprises frame segments 201 a, 201 b,201 c and 201 d disposed over substrate 102. In the illustratedembodiment, frame segments 201 a-d are substantially similar. Thefollowing description references the details of one or both of adjacentframe segments 201 a and 201 b, which may be applied to frame segments201 c and 201 d. All four frame segments 201 a-d comprises orthogonaledge members (e.g., 203 a and 204 a), which extend from a corner alongorthogonal edges of substrate 102. Elongate structural members 104extend from edge members (e.g., 203 a and 204 a) of frame segments 201a-d over substrate 102. In some embodiments, elongate structural members104 extend diagonally from edge members 203 and 204, imparting a righttriangular shape to frame segments 201 a-d. Corners of frame segments201 a-d may coincide with corners of substrate 102.

In some embodiments, frame segments 201 a-201 d comprise conductivematerials such as copper, nickel and beryllium. In some embodiments,frame segments comprise sheet metal comprising the copper, nickel andberyllium having thickness ranging from 100 to 500 microns.

Adjacent frame segments 201 a and 201 b comprise interlocking sections206 a and 206 b, located at the distal ends of edge members 203 a and203 b, respectively. Interlocking sections 206 a and 206 b compriseprotrusions 208 a and 208 b, respectively, which are interdigitated,forming an articulating hinge-like structure in an interlockinginterface 207. A magnified view is shown of interlocking interface 207(encircled within dashed circle). Interlocking interface 207 is sharedbetween frame segments 201 a and 201 b, where interlocking sections 206a and 206 b are respectively parts of mating frame segments 201 a and201 b.

In the illustrated embodiment of FIG. 2A, protrusions 208 a and 208 bhave a pointed shape. A zig-zag shaped boundary is betweeninterdigitated protrusions 208 a and 208 b. The structural features ofinterlocking interface 207 are substantially repeated by interlockinginterfaces 209, 210 and 211, where each interlocking interface couplesadjacent frame segments 201 a-b. Interlocking interfaces 209, 210 and211 are encompassed by the dashed circles on each edge of RF shieldframe 200. The zig-zag boundary between interdigitated protrusions 208 aand 208 b comprises a gap separated by a distance d₄. Interdigitatedprotrusions 208 a and 208 b restrict lateral movement of linked framesegments 201 a and 201 b. In some embodiments, distance d₄ is 50 micronsor less.

In some embodiments, the gap between interdigitated protrusions 208 aand 208 b functions as an articulating joint, allowing linked framesegments 201 a and 201 b to bend in the z-direction, following warpageof substrate 102.

While the above description has been confined to interlocking interface207, it is understood that in some embodiments, interlocking interfaces209, 210 and 211 comprise interdigitating protrusions that aresubstantially the same as or similar to interdigitating protrusions 208a and 208 b, having a pointed shape, and separated by zig-zagboundaries. Interlocking interfaces 209, 210 and 211 comprise gapssimilar to the gap shown in the magnified view of interlocking section207, having a separation distance substantially similar to d₄. In asubstantially similar manner, interlocking sections 209, 210 and 211respectively link together frame segments 201 b and 201 c; 201 c and 201d; and 201 d and 201 a. In some embodiments, at least one ofinterlocking interfaces 209, 210 and 211 comprises interdigitatingprotrusions having a shape that is substantially different thaninterdigitating protrusions 208 a and 208 b.

FIG. 2B illustrates a profile view in the x-z plane of RF shield frame200, according to some embodiments of the disclosure.

FIG. 2B shows details in the x-z plane of frame members 203 a and 203 bof frame segments 201 a and 201 b, respectively. In some embodiments,the details depicted in the view of FIG. 2B may be repeated for framemembers 201 c and 201 d, not shown in FIG. 2B. In the illustratedembodiment, the edges of substrate 102 are partially clad by portions offrame members 203 a and 203 b, which are folded into the x-z plane, andextend over the edges of substrate 102 a distance d₂ from the top ofsubstrate 102. Embossments 112 are shown in profile view on the topportions of edge members 203 a and 203 b of frame segments 201 a and 201b, respectively, extending a distance d₃ above edge members 203 a and203 b. In some embodiments, embossments 112 are provided to align withslots on a mating lid (described below and shown in FIG. 5A). In someembodiments, embossments 112 are omitted.

FIG. 3A illustrates a plan view in the x-y plane of RF shield frame 300,according to some embodiments of the disclosure.

In FIG. 3A, RF shield frame 300 comprises frame segments 301 a, 301 b,301 c and 301 d. In some embodiments, frame segments 301 a-d aresubstantially structurally similar. In some embodiments, RF shield frame300 has substantial symmetry. For clarity, therefor, structural detailsdescribed for structural members of frame segments 301 a and 301 b aregenerally repeatable for 301 c and 301 d. Frame segments 301 a and 301 bcomprise orthogonal edge members 303 a and 303 b, where edge member 303a extends orthogonally from edge member 303 b, according to someembodiments. In the illustrated embodiment, frame segments 301 a and 301b comprise elongate structural members 104 that extend diagonally oversubstrate 102 from edge members 303 b and 304 b. In some embodiments,elongate structural members 104 terminate at a common point. In someembodiments, pads 105 are disposed along elongate structural members104. As noted above (e.g., see discussion related to FIGS. 1A and 2A),pads 105 may be employed to provide a surface for pick-and-place nozzlesuction cup touch-down.

Frame segments 301 a and 301 b comprise interlocking sections 306 a and306 b at the distal end of edge members 303 a and 303 b, respectively,where interlocking sections 306 a and 306 b are interfaced. A magnifiedview is shown of interlocking interface 307 (within dashed circle). Inthe illustrated embodiment of FIG. 3A, protrusions 308 a and 308 b havea rectangular shape. A rectilinear meandering boundary is betweeninterdigitated protrusions 308 a and 308 b. Interlocking interfaces 309,310 and 311 are encompassed by the dashed circles on each edge of RFshield frame 300. The structural features of interlocking interface 307are substantially repeated by interlocking interfaces 309, 310 and 311,coupling frame segments 301 b and 301 d, 301 d with 301 c, and 301 cwith 301 a, respectively.

In some embodiments, frame segments 301 a-301 d comprise conductivematerials such as copper, nickel and beryllium. In some embodiments,frame segments comprise sheet metal comprising the copper, nickel andberyllium having thickness ranging from 100 to 500 microns.

The rectilinear meandering boundary between interdigitated protrusions308 a and 308 b comprises a gap separated by a distance d₅.Interdigitated protrusions 308 a and 308 b restrict lateral movement oflinked frame segments 301 a and 301 b. In some embodiments, distance d₅ranges between 0 and 50 microns. In some embodiments, interdigitatedprotrusions 308 a and 308 b together function as an articulating hinge,allowing linked frame segments 301 a and 301 b to bend in thez-direction, following warpage of substrate 102.

In some embodiments, frame members 301 a and 301 b comprise embossments112 distributed along at least one of edge members (e.g., 303 a and 303b). In some embodiments, embossments 112 are not present. Embossments112 are described in more detail below (FIG. 3B).

Interlocking interfaces 309, 310 and 311 comprise interdigitatingprotrusions that are substantially the same as interdigitatingprotrusions 308 a and 308 b, separated by rectilinear meanderingboundaries. Interlocking sections 309, 310 and 311 respectively linktogether frame segments 301 b and 301 d; 301 d and 301 c; and 301 c and301 a. In some embodiments, at least one of interlocking interfaces 309,310 and 311 comprises interdigitating protrusions having a shape that issubstantially different than interdigitating protrusions 308 a and 308b.

FIG. 3B illustrates a profile view in the x-z plane of RF shield frame300, according to some embodiments of the disclosure.

In the illustrated embodiments shown in the profile view of FIG. 3B,portions of edge members 303 a and 303 b are folded into the x-z planeover an edge of substrate 102. In some embodiments, the details shown inthe view of FIG. 3B for frame members 301 a and 301 b are repeated forframe members 301 c and 301 d, having edge members along the remainingthree edges of substrate 102, not shown. In some embodiments, edgemembers 303 a and 303 b extend in the x-z plane approximately distanced₂ from the top of substrate 102, corresponding to the thickness offrame members 301 a and 301 b.

Embossments 112 are shown in profile view extending a distance d₃ abovethe top portions of edge members 303 a and 303 b and 304 a and 304 b. Insome embodiments, embossments 112 are to align with slots on a mating RFshield lid (described below and shown in FIG. 5A). In some embodiments,embossments 112 are omitted.

FIG. 4A illustrates a plan view in the x-y plane of warpage-compensatingRF shield frame 400, according to embodiments of the disclosure.

In FIG. 4A, RF shield frame 400 comprises frame segments 401 a, 401 b,401 c and 401 d along corners of substrate 102. In some embodiments,frame segments 401 a-d are substantially similar. For the purposes ofclarity, the following description references the details of one or bothof adjacent frame segments 401 a and 401 b, which then may be applied toframe segment 401 c and 401 d. Frame segments 401 a-d compriseorthogonal edge members (e.g., 403 a and 404 a, 403 b and 404 b)disposed along one edge of substrate 102. In some embodiments, elongatestructural members 104 extend from edge members (e.g., 403 a and 404 a)over substrate 102. In some embodiments, elongate structural members 104extend diagonally from edge members (e.g., 403 a and 404 b), imparting aright triangular shape to frame segments 401 a-d. Corners of framesegments 401 a-d may coincide with corners of substrate 102.

Adjacent frame segments 401 a and 401 b comprise interlocking sections406 a and 406 b, located at the distal ends of edge members 403 a and403 b, respectively. Interlocking sections 406 a and 406 b compriseprotrusions 408 a and 408 b, respectively, which are interdigitated inthe illustrated embodiment, forming an articulating hinge. A magnifiedview is shown of interlocking interface 407 (encircled within dashedcircle).

In the embodiment illustrated in FIG. 4A, interlocking interface 407comprises interdigitating structures 408 a and 408 b in a lock and keyconfiguration. In some embodiments, interdigitating structure 408 a is aspoon-shaped tab extending from interlocking section 406 a.Interdigitating structure 408 a inserts into mating or dockinginterdigitating structure 408 b, disposed within interlocking section406 b.

Interdigitating structures 408 a and 408 b restrict lateral movement offrame segments 401 a and 401 b. In some embodiments, interlockinginterface comprises a gap separating interdigitating structures 408 aand 408 b by a distance d₆. In some embodiments, distance d₆ rangesbetween 0 and 50 microns.

The structural features of interlocking interface 407 may besubstantially repeated by interlocking interfaces 409, 410 and 411,respectively coupling frame segments 401 a with 401 d, 401 d with 401 c,and 401 c with 401 a. Interlocking interfaces 409, 410 and 411 areencompassed by the dashed circles on each edge of RF shield frame 400.

In some embodiments, frame segments 401 a-401 d comprise conductivematerials such as copper, nickel and beryllium. In some embodiments,frame segments comprise sheet metal comprising the copper, nickel andberyllium having thickness ranging from 100 to 500 microns.

FIG. 4B illustrates a profile view in the x-z plane ofwarpage-compensating RF shield frame 400, according to some embodimentsof the disclosure.

FIG. 4B shows details in the x-z plane of frame members 403 a and 403 bof frame segments 401 a and 401 b, respectively. In some embodiments,the details depicted in the view of FIG. 4B may be repeated for framemembers 401 c and 401 d, not shown in FIG. 4B. In the illustratedembodiment, the edges of substrate 102 are at least partially clad byportions of edge members 403 a and 403 b, which are folded into the x-zplane. Edge members 403 a and 403 b extend down from the top ofsubstrate 102 by a distance d₂, corresponding to the thickness of framemembers 401 a and 401 b, according to some embodiments. Embossments 112are shown in profile view extending over edge members 403 a and 403 b bya distance d₃. In some embodiments, embossments 112 are provided toalign with slots on a mating lid (not shown; described below and shownin FIG. 5A). In some embodiments, embossments 112 are omitted.

FIG. 5A illustrates a plan view in the x-y plane of awarpage-compensating RF shield assembly 500 comprising RF shield lid 501and RF shield frame 100, according to some embodiments of thedisclosure.

In FIG. 5A, warpage-compensating RF shield assembly 500 is shown asseparate parts comprising RF shield lid 501 and RF shield frame 100,related by the dashed lines. RF shield frame 100 is shown fullyassembled and mounted on package substrate 102. RF shield frame 100comprises elongate members 104 and pads 105 to facilitate assembly, asdescribed above. In the illustrated embodiment, RF shield lid 501comprises slots 502 that align with embossments 112 on RF shield frame100. In some embodiments, slots 502 and embossments 112 are omitted. Insome embodiments, RF shield lid 501 is to be press-fitted onto RF shieldframe 100. Details of the interaction between embossments 112 and slots502 are given below for FIG. 5C. In some embodiments, RF shield lid 500comprise conductive materials such as copper, nickel and beryllium. Insome embodiments, RF shield lid comprises sheet metal comprising thecopper, nickel and beryllium having thickness ranging from 100 to 500microns.

Referring again to FIG. 5A, substrate 102 comprises IC die 504 attachedsubstantially at the center of substrate 102. In some embodiments,multiple dies are attached to substrate 102. Elongate members 104 may bearranged in different configurations to accommodate various die layouts.In order to accommodate RF shield lid 501, IC die 504 may have athickness no greater than the thickness of the structural elements of RFshield frame 100.

FIG. 5B illustrates an exploded view of separate components ofcomprising RF shield lid 501 and RF shield frame 100 of RF shieldassembly 500 in the x-z plane, according to some embodiments of thedisclosure.

In FIG. 5B, lateral edges of RF shield lid 501 are aligned with lateraledges of RF shield frame 100, as indicated by the dashed connectorlines. RF shield frame 100 is shown mounted on substrate 102. In someembodiments, edge 503 of RF shield lid 501 is to slide over edge members103 a and 103 b of RF shield frame 100. A profile outline of an IC die(e.g., IC die 504 in FIG. 5A) is shown as a hidden dashed rectanglecentered over substrate 102 just below the top of frame members 103 aand 103 b. In the illustrated embodiment, the IC die profile does notexceed the clearance of the sheet metal thickness of frame members 103 aand 103 b (e.g., distance d₃ in FIG. 3B).

FIG. 5C illustrates a profile view in the x-z plane of RF shieldassembly 500 in the assembled state, according to some embodiments ofthe disclosure. Embossments 112 extend a distance d₇ above the top of RFshield frame 100 (shown in hidden dashed line below the top of RF shieldlid 501). In some embodiments, d₇ may be several hundred microns,including the thickness of the sheet metal of RF shield frame 100. Insome embodiments, distance d₇ ranges between 100 and 500 microns, andincludes clearance for an attached IC die, (e.g., IC die 504 in FIG.5A), indicated by the dashed hidden rectangle centered on the topsurface of substrate 102 (indicated by the dashed hidden line below lidtop 505). In some embodiments, RF shield lid 501 is attached by apress-fit process onto RF shield frame 100. In some embodiments,embossments 112 are omitted. RF shield lid 503 may rest on RF shieldframe 100 with some lateral tolerance.

Soldering or welding lid 501 to frame 100 may restrict or prevent framesegments from following out-of-plane warpage of corners or otherportions of substrate 102. Embossments 112 provide RF shield lid 501with a plurality of intimate contact points with RF shield frame 100 byvirtue of the ability of embossments 112 to slide vertically withinslots 502. When substrate 102 undergoes warpage, the corners typicallywarp out of the x-y plane, causing individual frame segments of RFshield frame 100 to follow this warpage substrate 102 by articulatingabout the interdigitated joints without unduly straining any solderjoints between RF shield frame 100 and substrate 102, creating opensolder joints.

RF shield 500 is generally grounded through substrate 102. Open solderjoints between RF shield lid 501 and RF shield frame 100 maysignificantly reduce the effectiveness of RF shield assembly 500 againstEMI and RFI emanating from the integrated circuit generating the RF. Insome embodiments, embossments 112 extend in the z-direction throughslots 502 by several hundred microns, allowing RF shield assembly 500 totolerate significant warpage of substrate 102.

FIG. 6 illustrates flow chart 600, summarizing an exemplary method forforming a RF shield frame according to some embodiments of thedisclosure.

At operation 601, a package substrate (e.g., substrate 102) is receivedfor attachment of the RF shield according to the some of the embodimentsof the disclosure. The state of assembly of the package may includeattachment of IC dies onto the substrate. In some embodiments othercomponents, such as a stiffener, are attached.

At operation 602, pre-reflow solder points are applied to the substrate.The substrate may be bumped with solder balls, or points of solder pastemay be applied along the edges and at points on the interior region ofthe substrate. Solder points may be applied over ground metallization onthe substrate, such as a ground plane and/or ground traces.

At operation 603, the RF shield frame is assembled onto the substrate.The RF shield frame is assembled by placement of frame segments. Inexemplary embodiments, four frame segments are placed at each corner ofthe substrate either one-by-one, or all four simultaneously. The framesegments are assembled so that articulating joints are made by linkinginterlocking sections by interdigitation. Pick-and-place operations maybe employed to manipulate the frame segments and assemble them on thesubstrate. In some embodiments, frame segments are assembled one at atime. In some embodiments, frame segments are placed and assembledsimultaneously.

At operation 604, the substrate is subjected to solder reflowtemperatures in order to melt the solder points, and reflowing thesolder to form bonds between the RF shield frame segments to thesubstrate. During reflow, interlocking joints (e.g., the joint formed byinterdigitating protrusions 108 a and 108 b in FIG. 1A) restrict lateralmovement of the individual frame segments, which may float on the liquidsolder. Interlocking joints between frame segment restrict lateralseparation of the individual frame segments, which may move laterallyand may fall off of the substrate. Minor lateral motion of the framesegments may cause edge members to overhang the substrate, exceedingpackage dimensional tolerances in the x and/or y dimensions.

At operation 605, a RF shield lid (e.g., RF shield lid 504 in FIGS.5A-5C) is attached to the bonded RF shield frame. In some embodiments,the RF shield frame comprises embossments (e.g., 112 in FIG. 1A) thatare aligned with slots or apertures in the RF shield lid. In someembodiments, the RF shield lid is press-fit onto the RF shield frame.The attachment of the lid completes the assembly RF shield (e.g., 500 inFIG. 5C) on the package substrate.

At operation 606, the package substrate comprising the RF shield ispassed on to downstream package assembly operations (e.g., packagecomponent attachment, encapsulation).

FIGS. 7A-7G illustrate a progression of operations expanding upon theexemplary method shown in FIG. 6 for making warpage compensating RFshield frame 100, according to some embodiments of the disclosure.

In the operation depicted in FIG. 7A, package substrate 102 is receivedpartially assembled. For clarity, only metallization layer 701 overdielectric 602 is shown to represent package substrate 102 as receivedfor assembly of a warpage-compensating RF shield frame, according tosome embodiments. In some embodiments, package substrate 102 as receivedcomprises mounted components such as IC dies, discrete components,stiffeners, etc. Metallization layer 701 may be part of the groundcircuitry. In some embodiments, metallization layer 701 comprises aground plane and traces coupled to the ground plane. In someembodiments, metallization layer 701 comprises traces electricallycoupled to metal structures to be electrically coupled to groundcircuitry.

In the operation depicted in FIG. 7B, solder points 703 are dispensedover portions of metallization layer 701. In some embodiments, solderpoints 703 are boules of semi-solid solder paste. In some embodiments,solder points 703 are solder balls or bumps. Solder points may bedispensed on package substrate 102 by established methods known in theindustry. Solder points 703 are to be reflowed subsequently.

In the operation depicted in FIG. 7C, RF shield frame 100 assemblybegins with placement of frame segment 103 a on substrate 102. In theillustrated embodiment, frame segment 103 a is the first of four framesegments (e.g., frame segments 103 a-d in FIG. 1A) to be placed onsubstrate 102 for the assembly of RF shield frame 100 (see FIGS. 1A and1B for structural details). However, the assembly process of RF shieldframe 100 described herein is not limited to any particular order ofpart placement. Frame segments 103 a-d may be assembled together inrandom order.

Any suitable method may be employed to place frame segment 103 a (andthe subsequent frame segments) on substrate 102. In some embodiments, anautomated pick-and-place tool is employed to pick up frame segment partsand align them over substrate 102. Referring to FIG. 1A, someembodiments of RF shield frame 100 comprise pads 105, which provide acontact surface for a pick-and-place suction interface.

Returning to FIG. 7C, frame segment 103 a is first aligned oversubstrate 102. In some embodiments, corner 704 of frame segment 103 a isaligned with corner 705 of substrate 102. Frame segment 103 a is alsoaligned with edge 706 of substrate 102. Down-pointing arrows indicatelowering of frame segment 103 a to touch down on solder points 703.

In the operation depicted in FIG. 7D, frame segment 103 b is aligned andplaced over substrate 102 subsequent to frame segment 103 a. Asmentioned above, the order of frame segment placement is not limited toany particular order or that depicted in the operation sequence shown inFIGS. 7C and 7D. In a manner similar to the operation of FIG. 7C, framesegment 103 b is first aligned over substrate 102. In some embodiments,corner 707 of frame segment 103 b is aligned with corner 708 and edge706 of substrate 102. Additionally, frame segment 103 b is aligned insuch a way that interlocking segments 106 a and 106 b are aligned.

Interlocking segments 106 a and 106 b comprise interdigitatingprotrusions 108 a and 108 b (e.g., FIG. 1A). Referring back to FIG. 7D,the alignment operation of frame segments 103 a and 103 b is performedso that protrusions 108 a and 108 b (not shown) are interdigitated whenframe segment 103 b is lowered (indicated by down-pointing arrows) ontosolder points 703. The operation creates an interlocking interfacebetween frame segments 103 a and 103 b.

Remaining frame segments 103 c and 103 d may be added in any order tothe assembly of RF shield frame 100 in two subsequent operations,similar to the operation depicted in FIG. 7D for frame segment 103 b. Asan example, frame segment 103 c (not shown) is aligned with a thirdcorner and edge of substrate 102, below the plane of the figure. Theinterlocking sections of both frame segment 103 c and that of framesegment 103 b (interlocking section 106 b) are aligned. Frame segment103 c is then placed over substrate 102 to form an interlockinginterface with frame segment 103 b. Frame segment 103 d is aligned witha fourth corner and edge of substrate 102, as well as alignment of theinterlocking sections of frame segments 103 c and 103 a. Frame segment103 d forms an interlocking interface with both frame segment 103 c and103 a as frame segment is placed over substrate 102.

In the operation depicted in FIG. 7E, RF shield fame 100 is assembled.FIG. 1A shows the finished assembly in the x-y plane. A reflow operationis performed to solder frame segments to substrate 102 causing reflow ofsolder points 703, hidden from the view of the figure under framesegments 103 a and 103 b. The reflow operation may be performed in areflow oven or in a thermal compression bonder.

In the operation depicted in FIG. 7F, RF shield lid 500 (see FIGS. 5Aand 5B) is aligned and placed over RF shield frame 100. In someembodiments, shield lid 500 comprises slots on the top (in the x-yplane, FIG. 5A) that align with embossments 112. In some embodiments, RFshield lid 500 is press fit to RF shield frame 100 (see discussion forFIG. 5B).

In FIG. 7G, assembly of RF shield 501 is completed. RF shield lid 500 isattached to RF shield frame 100 (FIG. 5C).

FIG. 8 illustrates an IC package having a warpage-compensating RF shield(e.g., 500 in FIG. 5A-5C), fabricated according to the disclosed method,as part of a system-on-chip (SoC) package in an implementation ofcomputing device, according to some embodiments of the disclosure.

FIG. 8 illustrates a block diagram of an embodiment of a mobile devicein which flat surface interface connectors could be used. In someembodiments, computing device 800 represents a mobile computing device,such as a computing tablet, a mobile phone or smart-phone, awireless-enabled e-reader, or other wireless mobile device. It will beunderstood that certain components are shown generally, and not allcomponents of such a device are shown in computing device 800.

In some embodiments, computing device 800 includes a first processor810. The various embodiments of the present disclosure may also comprisea network interface within 870 such as a wireless interface so that asystem embodiment may be incorporated into a wireless device, forexample, cell phone or personal digital assistant.

In one embodiment, processor 810 can include one or more physicaldevices, such as microprocessors, application processors,microcontrollers, programmable logic devices, or other processing means.The processing operations performed by processor 810 include theexecution of an operating platform or operating system on whichapplications and/or device functions are executed. The processingoperations include operations related to I/O (input/output) with a humanuser or with other devices, operations related to power management,and/or operations related to connecting the computing device 800 toanother device. The processing operations may also include operationsrelated to audio I/O and/or display I/O.

In one embodiment, computing device 800 includes audio subsystem 820,which represents hardware (e.g., audio hardware and audio circuits) andsoftware (e.g., drivers, codecs) components associated with providingaudio functions to the computing device. Audio functions can includespeaker and/or headphone output, as well as microphone input. Devicesfor such functions can be integrated into computing device 800, orconnected to the computing device 800. In one embodiment, a userinteracts with the computing device 800 by providing audio commands thatare received and processed by processor 810.

Display subsystem 830 represents hardware (e.g., display devices) andsoftware (e.g., drivers) components that provide a visual and/or tactiledisplay for a user to interact with the computing device 800. Displaysubsystem 830 includes display interface 832 which includes theparticular screen or hardware device used to provide a display to auser. In one embodiment, display interface 832 includes logic separatefrom processor 810 to perform at least some processing related to thedisplay. In one embodiment, display subsystem 830 includes a touchscreen (or touch pad) device that provides both output and input to auser.

I/O controller 840 represents hardware devices and software componentsrelated to interaction with a user. I/O controller 840 is operable tomanage hardware that is part of audio subsystem 820 and/or displaysubsystem 830. Additionally, I/O controller 840 illustrates a connectionpoint for additional devices that connect to computing device 800through which a user might interact with the system. For example,devices that can be attached to the computing device 800 might includemicrophone devices, speaker or stereo systems, video systems or otherdisplay devices, keyboard or keypad devices, or other I/O devices foruse with specific applications such as card readers or other devices.

As mentioned above, I/O controller 840 can interact with audio subsystem820 and/or display subsystem 830. For example, input through amicrophone or other audio device can provide input or commands for oneor more applications or functions of the computing device 800.Additionally, audio output can be provided instead of, or in addition todisplay output. In another example, if display subsystem 830 includes atouch screen, the display device also acts as an input device, which canbe at least partially managed by I/O controller 840. There can also beadditional buttons or switches on the computing device 800 to provideI/O functions managed by I/O controller 840.

In one embodiment, I/O controller 840 manages devices such asaccelerometers, cameras, light sensors or other environmental sensors,or other hardware that can be included in the computing device 800. Theinput can be part of direct user interaction, as well as providingenvironmental input to the system to influence its operations (such asfiltering for noise, adjusting displays for brightness detection,applying a flash for a camera, or other features).

In one embodiment, computing device 800 includes power management 850that manages battery power usage, charging of the battery, and featuresrelated to power saving operation. Memory subsystem 860 includes memorydevices for storing information in computing device 800. Memory caninclude nonvolatile (state does not change if power to the memory deviceis interrupted) and/or volatile (state is indeterminate if power to thememory device is interrupted) memory devices. Memory subsystem 860 canstore application data, user data, music, photos, documents, or otherdata, as well as system data (whether long-term or temporary) related tothe execution of the applications and functions of the computing device800.

Elements of embodiments are also provided as a machine-readable medium(e.g., memory 860) for storing the computer-executable instructions. Themachine-readable medium (e.g., memory 860) may include, but is notlimited to, flash memory, optical disks, CD-ROMs, DVD ROMs, RAMs,EPROMs, EEPROMs, magnetic or optical cards, phase change memory (PCM),or other types of machine-readable media suitable for storing electronicor computer-executable instructions. For example, embodiments of thedisclosure may be downloaded as a computer program (e.g., BIOS) whichmay be transferred from a remote computer (e.g., a server) to arequesting computer (e.g., a client) by way of data signals via acommunication link (e.g., a modem or network connection).

Connectivity via network interface 870 includes hardware devices (e.g.,wireless and/or wired connectors and communication hardware) andsoftware components (e.g., drivers, protocol stacks) to enable thecomputing device 800 to communicate with external devices. The computingdevice 800 could be separate devices, such as other computing devices,wireless access points or base stations, as well as peripherals such asheadsets, printers, or other devices.

Network interface 870 can include multiple different types ofconnectivity. To generalize, the computing device 800 is illustratedwith cellular connectivity 872 and wireless connectivity 874. Cellularconnectivity 872 refers generally to cellular network connectivityprovided by wireless carriers, such as provided via GSM (global systemfor mobile communications) or variations or derivatives, CDMA (codedivision multiple access) or variations or derivatives, TDM (timedivision multiplexing) or variations or derivatives, or other cellularservice standards. Wireless connectivity (or wireless interface) 874refers to wireless connectivity that is not cellular, and can includepersonal area networks (such as Bluetooth, Near Field, etc.), local areanetworks (such as Wi-Fi), and/or wide area networks (such as WiMax), orother wireless communication.

Peripheral connections 880 include hardware interfaces and connectors,as well as software components (e.g., drivers, protocol stacks) to makeperipheral connections. It will be understood that the computing device800 could both be a peripheral device (“to” 882) to other computingdevices, as well as have peripheral devices (“from” 884) connected toit. The computing device 800 commonly has a “docking” connector toconnect to other computing devices for purposes such as managing (e.g.,downloading and/or uploading, changing, synchronizing) content oncomputing device 800. Additionally, a docking connector can allowcomputing device 800 to connect to certain peripherals that allow thecomputing device 800 to control content output, for example, toaudiovisual or other systems.

In addition to a proprietary docking connector or other proprietaryconnection hardware, the computing device 800 can make peripheralconnections 880 via common or standards-based connectors. Common typescan include a Universal Serial Bus (USB) connector (which can includeany of a number of different hardware interfaces), DisplayPort includingMiniDisplayPort (MDP), High Definition Multimedia Interface (HDMI),Firewire, or other types.

Reference in the specification to “an embodiment,” “one embodiment,”“some embodiments,” or “other embodiments” means that a particularfeature, structure, or characteristic described in connection with theembodiments is included in at least some embodiments, but notnecessarily all embodiments. The various appearances of “an embodiment,”“one embodiment,” or “some embodiments” are not necessarily allreferring to the same embodiments. If the specification states acomponent, feature, structure, or characteristic “may,” “might,” or“could” be included, that particular component, feature, structure, orcharacteristic is not required to be included. If the specification orclaim refers to “a” or “an” element, that does not mean there is onlyone of the elements. If the specification or claims refer to “anadditional” element, that does not preclude there being more than one ofthe additional element.

Furthermore, the particular features, structures, functions, orcharacteristics may be combined in any suitable manner in one or moreembodiments. For example, a first embodiment may be combined with asecond embodiment anywhere the particular features, structures,functions, or characteristics associated with the two embodiments arenot mutually exclusive.

While the disclosure has been described in conjunction with specificembodiments thereof, many alternatives, modifications and variations ofsuch embodiments will be apparent to those of ordinary skill in the artin light of the foregoing description. The embodiments of the disclosureare intended to embrace all such alternatives, modifications, andvariations as to fall within the broad scope of the appended claims.

In addition, well known power/ground connections to integrated circuit(IC) chips and other components may or may not be shown within thepresented figures, for simplicity of illustration and discussion, and soas not to obscure the disclosure. Further, arrangements may be shown inblock diagram form in order to avoid obscuring the disclosure, and alsoin view of the fact that specifics with respect to implementation ofsuch block diagram arrangements are highly dependent upon the platformwithin which the present disclosure is to be implemented (i.e., suchspecifics should be well within purview of one skilled in the art).Where specific details (e.g., circuits) are set forth in order todescribe example embodiments of the disclosure, it should be apparent toone skilled in the art that the disclosure can be practiced without, orwith variation of, these specific details. The description is thus to beregarded as illustrative instead of limiting.

An abstract is provided that will allow the reader to ascertain thenature and gist of the technical disclosure. The abstract is submittedwith the understanding that it will not be used to limit the scope ormeaning of the claims. The following claims are hereby incorporated intothe detailed description, with each claim standing on its own as aseparate embodiment.

1. An integrated circuit package shield comprising: a frame comprisingtwo or more interlocking segments to extend along a substrate, thesegments comprising one or more first electrically conductive materialsto electrically couple to the substrate; and a lid to cover the frame,the lid comprising one or more second electrically conductive materialsto electrically couple to the substrate.
 2. The integrated circuitpackage shield of claim 1, wherein a first segment comprises a firstinterlocking section to interface with a second segment and a secondinterlocking section to interface with a third segment, the firstinterlocking section to restrict movement of the first segment in afirst direction and the second interlocking section to restrict movementof the first segment in a second direction unaligned with the firstdirection.
 3. The integrated circuit package shield of claim 2, whereinthe first direction and the second direction are substantiallyorthogonal.
 4. The integrated circuit package shield of claim 2, whereinthe second segment comprises a third interlocking section to interfacewith the first interlocking section and the third segment comprises afourth interlocking section to interface with the second interlockingsection.
 5. The integrated circuit package shield of claim 2, whereinthe frame further comprises a fourth segment, wherein the fourth segmentcomprises a fifth interlocking section to interface with the secondsegment, and a sixth interlocking section to interface with the thirdsegment, and wherein the fifth interlocking section is to restrictmovement of the fourth segment in a first direction and the sixthinterlocking section is to restrict movement of the fourth segment in asecond direction that is unaligned with the first direction.
 6. Theintegrated circuit package shield of claim 1, wherein a first segmentcomprises a first interlocking section to interface with a secondinterlocking section of a second segment, wherein the first interlockingsection comprises one or more first protrusions to interdigitate withone or more second protrusions of the interlocking section.
 7. Theintegrated circuit package shield of claim 6, wherein the interdigitatedfirst and second protrusions comprise a meandering boundary, themeandering boundary to extend from an edge of the substrate to a firstdistance the frame extends over the substrate.
 8. The integrated circuitpackage shield of claim 6, wherein the interdigitated first and secondprotrusions comprise a zig-zag shaped boundary.
 9. The integratedcircuit package shield of claim 6, wherein the interdigitated first andsecond protrusions comprise a rectangular shape.
 10. The integratedcircuit package shield of claim 6, wherein the interdigitated first andsecond protrusions comprise a lock and key configuration.
 11. Theintegrated circuit package shield of claim 1, wherein the two or moresegments comprise two or more elongate members that extend over thesubstrate, and wherein the two or more elongate members intersect.
 12. Asystem comprising: an integrated circuit die coupled to a substrate; ashield surrounding the integrated circuit die, the shield comprising: aframe laterally surrounding the integrated circuit die, the framecomprising two or more interlocking segments, the segments comprisingone or more first electrically conductive materials electrically coupledto the substrate; and a lid over the integrated circuit die and theframe, the lid comprising one or more second electrically conductivematerials electrically coupled to the substrate.
 13. The system of claim12, wherein the substrate comprises a ground plane, and wherein thesegments are electrically coupled to the ground plane.
 14. The system ofclaim 13, wherein the segments are electrically coupled to the groundplane by solder joints.
 15. The system of claim 12, wherein the framecomprises one or more embossments along at least one edge of the frame,wherein the lid comprises at least one edge and one or more perforationsproximal to the at least one edge, and wherein the one or moreperforations are to align with the one or more embossments, such thatthe movement of the lid relative to the frame is restricted in twoorthogonal directions.
 16. An integrated circuit package shieldcomprising: a frame comprising a plurality of conductive interlockingsegments, each of the segments comprising an interlocking section tointerface with another interlocking section of another segment, thesegments electrically coupled to a substrate; and a lid to cover theframe, the lid comprising one or more electrically conductive materialsto electrically couple to the substrate.
 17. The integrated circuitpackage shield of claim 16, wherein a first segment comprises a firstinterlocking section to interface with a second segment and a secondinterlocking section to interface with a third segment, the firstinterlocking section to restrict movement of the first segment in afirst direction and the second interlocking section to restrict movementof the first segment in a second direction unaligned with the firstdirection.
 18. The integrated circuit package shield of claim 16,wherein a first segment comprises a first interlocking section tointerface with a second interlocking section of a second segment,wherein the first interlocking section comprises one or more firstprotrusions to interdigitate with one or more second protrusions of theinterlocking section.
 19. The integrated circuit package shield of claim18, wherein the interdigitated first and second protrusions comprise oneof a meandering boundary, a zig-zag shaped boundary, a rectangularshape, or a lock and key configuration.
 20. The integrated circuitpackage shield of claim 16, wherein a first segment comprises two ormore elongate members that extend over the substrate, and wherein thetwo or more elongate members intersect.